Showing 3891 - 3900 of 5713 Items
Correcting in situ chlorophyll fluorescence time-series observations for nonphotochemical quenching and tidal variability reveals nonconservative phytoplankton variability in coastal waters
Date: 2019-08-01
Creator: Luke Carberry, Collin Roesler, Susan Drapeau
Access: Open access
- Chlorophyll fluorometry is one of the most commonly implemented approaches for estimating phytoplankton biomass in situ, despite documented sources of natural variability and instrumental uncertainty in the relationship between in vivo fluorescence and chlorophyll concentration. A number of strategies are employed to minimize errors and quantify natural variability in this relationship in the open ocean. However, the assumptions underlying these approaches are unsupported in coastal waters due to the short temporal and small spatial scales of variability, as well as the optical complexity. The largest source of variability in the in situ chlorophyll fluorometric signal is nonphotochemical quenching (NPQ). Typically, unquenched nighttime observations are interpolated over the quenched daytime interval, but this assumes a spatial homogeneity not found in tidally impacted coastal waters. Here, we present a model that provides a tidally resolved correction for NPQ in moored chlorophyll fluorescence measurements. The output of the model is a time series of unquenched chlorophyll fluorescence in tidal endmembers (high and low tide extremes), and thus a time series of phytoplankton biomass growth and loss in these endmember populations. Comparison between modeled and measured unquenched time series yields quantification of nonconservative variations in phytoplankton biomass. Tidally modeled interpolation between these endmember time series yields a highly resolved time series of unquenched daytime chlorophyll fluorescence values at the location of the moored sensor. Such data sets provide a critical opportunity for validating the satellite remotely sensed ocean color chlorophyll concentration data product in coastal waters.
An architecture for emotional decision-making agents
Date: 2002-01-01
Creator: Eric Chown, Randolph M. Jones, Amy E. Henninger
Access: Open access
- Our research focuses on complex agents that are capable of interacting with their environments in ways that are increasingly similar to individual humans. In this article we describe a cognitive architecture for an interactive decision-making agent with emotions. The primary goal of this work is to make the decision-making process of complex agents more realistic with regard to the behavior moderators, including emotional factors that affect humans. Instead of uniform agents that rely entirely on a deterministic body of expertise to make their decisions, the decision making process of our agents will vary according to select emotional factors affecting the agent as well as the agent's parameterized emotional profile. The premise of this model is that emotions serve as a kind of automatic assessment system that can guide or otherwise influence the more deliberative decision making process. The primary components of this emotional system are pleasure/pain and clarity/confusion subsystems that differentiate between positive and negative states. These, in turn, feed into an arousal system that interfaces with the decision-making system. We are testing our model using synthetic special-forces agents in a reconnaissance simulation.
RoboGrams: A lightweight message passing architecture for RoboCup soccer
Date: 2015-01-01
Creator: Elizabeth Mamantov, William Silver, William Dawson, Eric Chown
Access: Open access
- RoboGrams is a lightweight and efficient message passing architecture that we designed for the RoboCup domain and that has been successfully used by the Northern Bites SPL team. This unique architecture provides a framework for separating code into strongly decoupled modules, which are combined into configurable dataflow graphs. We present several different architecture types and preexisting message passing implementations, but among all of these, we contend that Robo-Grams' features make it particularly well suited for use in RoboCup. As a success story, we describe the Northern Bites' use of RoboGrams and the benefits it has provided to a single team, but we also suggest that it could help SPL teams collaborate in the future.
The History of Bowdoin College
Date: 1927-01-01
Creator: Louis Clinton Hatch
Access: Open access
- The History of Bowdoin College (1927), by Louis Clinton Hatch, is the most detailed history of the College for the period from the College’s founding in 1794 until 1927. It is especially useful in documenting College traditions and curricular developments, and tangentially in recording social life in Brunswick.
Interview with Justin Foster (Class of 2011) by Marina Henke
Date: 2019-11-10
Creator: Justin Foster
Access: Open access
- Justin Foster ('11) speaks of his time at Bowdoin primarily embodied through his experience with acapella. He describes how his passion for music carried him through Bowdoin. and also gave him room to try to bridge gaps and have conversations with students who were different from him. Foster also describes his relationship with AfAm, and outlines his personal choice to maintain deep connections outside of singularly all black spaces on campus. He expresses the conflictions that came from this decision, and the conversations that it then struck up with other students of color. Specifically, Foster describres certain highlights of his time in the Longfellows, including various performances across the country.
Descriptive Catalogue of the Art Collections of Bowdoin College
Date: 1906-01-01
Creator: Henry Johnson
Access: Open access
- 3d ed., rev. and enl
Lankapura: The Legacy of the Ramayana in Sri Lanka
Date: 2019-01-01
Creator: Justin W. Henry, Sree Padma
Access: Open access
- The five articles which make up this special issue of South Asia explore the role of the Ramayana in Sri Lankan art, literature, religious ritual and political discourse in shaping Sinhala Buddhist and Tamil Saiva perceptions of the island’s distant past. Contributors work to answer the question as to when and how Sri Lanka came to be equated with the mythic ‘Lankapura’ of Valmiki’s epic, exploring both positive and negative portrayals of Ravana (ruler of Lanka antagonist of the Ramayana) in Sinhala and Tamil literature from the late medieval period to the present day. Authors work to account for the politicisation and historicisation of the Ramayana in twenty-first century Sri Lanka (including similarities to and differences from the contemporary Indian situation), along with the appropriation of Ravana as a Sinhala Buddhist cultural hero, and the incorporation of Vibhishana as a ‘guardian deity’ in the Sinhala Buddhist pantheon.
Spirit of the New Landscape
Date: 1978-01-01
Access: Open access
- Catalog of an exhibition held Jan. 20-Mar. 12, 1978 at the Bowdoin College Museum of Art.
Art of Winslow Homer: An Exhibition of Paintings
Date: 1954-01-01
Access: Open access
- Catalog of an exhibition held at the Bowdoin College Museum of Art Nov. 1-21, 1954 and at the Women's Union of Colby College, Dec. 1-21, 1954.